21005709

Names of 21005709

• Cardinal: 21005709 can be written as Twenty-one million, five thousand, seven hundred nine.

Scientific notation

• Scientific notation: 2.1005709 × 10⁷

Factors of 21005709

• Number of distinct prime factors ω(n): 3
• Total number of prime factors Ω(n): 3
• Sum of prime factors: 10827

Divisors of 21005709

• Number of divisors d(n): 8
• Complete list of divisors:
  1 3 691 2073 10133 30399 7001903 21005709
• Sum of all divisors σ(n): 28050912
• Sum of proper divisors (its aliquot sum) s(n): 7045203
• 21005709 is a deficient number, because the sum of its proper divisors (7045203) is less than itself. Its deficiency is 13960506

Bases of 21005709

• Binary: 1010000001000010110001101₂
• Hexadecimal: 0x140858D
• Base-36: CI83X

Squares and roots of 21005709

• 21005709 squared (21005709²) is 441239810592681
• 21005709 cubed (21005709³) is 9268555060524974615829
• The square root of 21005709 is 4583.1985555941
• The cube root of 21005709 is 275.9174164811

Scales and comparisons

• 21,005,709 seconds is equal to 34 weeks, 5 days, 2 hours, 55 minutes, 9 seconds.
• To count from 1 to 21,005,709 would take you about sixteen hours!

  This is a very rough estimate, based on a speaking rate of half a second every third order of magnitude. If you speak quickly, you could probably say any randomly-chosen number between one and a thousand in around half a second. Very big numbers obviously take longer to say, so we add half a second for every extra x1000. (We do not count involuntary pauses, bathroom breaks or the necessity of sleep in our calculation!)

• A cube with a volume of 21005709 cubic inches would be around 23 feet tall.

Recreational maths with 21005709

• 21005709 backwards is 90750012
• The number of decimal digits it has is: 8
• The sum of 21005709's digits is 24
• More coming soon!